Physics of the Solid State最新文献

{"title":"A Comparative Study of the Structural, Electronic, and Optical Properties of GaAs Phases Using Different Exchange-Correlation Functionals","authors":"Sadegh Mohammadpour Lima","doi":"10.1134/S1063783424601346","DOIUrl":"10.1134/S1063783424601346","url":null,"abstract":"<p>We conducted first-principles calculations using density functional theory (DFT) to explore the structural, electronic, and optical characteristics of gallium arsenide (GaAs) in its wurtzite (WZ), zinc-blende (ZB), and rock-salt (RS) crystalline forms. These studies were carried out employing the full potential-linearized augmented plane wave (FP-LAPW) approach within the Wien2k computational framework. For the exchange-correlation (XC) potentials, we utilized various functionals including the local density approximation (LDA), generalized gradient approximation (PBE), Perdew–Burke–Ernzerhof for solids (PBEsol), modified Becke–Johnson (MBJ), and the strongly constrained and appropriately normed (SCAN) meta-generalized gradient approximation (meta-GGA). These functionals were applied to determine key physical properties such as equilibrium lattice constants, cell volume, bulk modulus, pressure derivatives, and energy band gaps. Additionally, we assessed optical features including dielectric and loss functions, refractive and extinction indices, and optical conductivity across the WZ, ZB, and RS phases. Our findings indicate that the structural and optical parameters derived from the SCAN meta-GGA functional show remarkable consistency with experimental observations, although it tends to underestimate the energy band gap. The most accurate predictions for the energy gap were achieved using the MBJ-PBEsol approach, aligning closely with experimental data.</p>","PeriodicalId":731,"journal":{"name":"Physics of the Solid State","volume":"66 11","pages":"543 - 555"},"PeriodicalIF":0.9,"publicationDate":"2024-11-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142636963","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Green and Chemical Synthesis of Silver Nanoparticles: A Comparative Study for Optical, Morphological, Structural, and Antibacterial Activities","authors":"P. Jamila Jayanthi,&nbsp;I. Kartharinal Punithavathy,&nbsp;A. Muthuvel,&nbsp;M. Jothibas,&nbsp;S. Johnson Jeyakumar,&nbsp;Rafa Almeer","doi":"10.1134/S1063783424601097","DOIUrl":"10.1134/S1063783424601097","url":null,"abstract":"<p>Two different methods (chemical and biological) are used to synthesize silver nanoparticles in this study. Silver nitrate was reduced using NaOH in a chemical method, while in a biological approach, Ag ions were reduced with an aqueous leaf extract of <i>Tridax procumbens</i>. Both types of synthesized nanoparticles were characterized using FT-IR, UV-Visible, XRD, PL, DLS, ZE, and SEM with EDAX. The X-ray diffraction (XRD) patterns established the incidence of a crystalline face centred cubic (FCC) structure in both nanoparticles samples. The average nanoparticles sizes were 29 nm for the chemically produced nanoparticles and 18 nm for the biologically synthesized ones. SEM analysis revealed a spherical shape for both types of nanoparticles, with average sizes of 36 nm for the chemically produced and 25 nm for the biologically synthesized nanoparticles. The surface plasmon resonance (SPR) peaks were observed at 384 nm for the chemically synthesized nanoparticles and at 424 nm for the biologically synthesized ones. FT-IR analysis indicated that O–H, C=O, and C–O–C functional groups were involved in the formation of Ag nanoparticles, with a zeta potential of –27.83 eV, exhibited long-term stability and resistance to agglomeration compared to the chemically synthesized nanoparticles, which had a zeta potential of –9.46 eV. Photoluminescence (PL) analysis demonstrated an enhanced visible spectrum for the nanoparticles. Additionally, the antibacterial activity tests showed that the biosynthesized Ag nanoparticles were more effective than the chemically synthesized ones. This enhanced activity was attributed to the protein capping and the mode of entry into bacterial cells, making the biosynthesized nanoparticles more potent. The study concluded that biosynthesized Ag nanoparticles exhibit a smaller crystalline size, better morphology, and more significant antimicrobial activity compared to their chemically synthesized counterparts.</p>","PeriodicalId":731,"journal":{"name":"Physics of the Solid State","volume":"66 11","pages":"476 - 483"},"PeriodicalIF":0.9,"publicationDate":"2024-11-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142636850","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Transport Properties of Layered Heterostructures on the Base of a Conducting Polymer","authors":"K. Yu. Arutyunov,&nbsp;K. A. Belyaev,&nbsp;V. V. Artemov,&nbsp;A. L. Vasil’ev,&nbsp;A. R. Yusupov,&nbsp;D. D. Karamov,&nbsp;A. N. Lachinov","doi":"10.1134/S1063783422120010","DOIUrl":"10.1134/S1063783422120010","url":null,"abstract":"<p>Polydiphenilenphtalide (PDP) belongs to organic dielectrics that demonstrate the electroconducting properties, when applying an external electrostatic field and/or mechanical stresses. In this work, the transport characteristics of thin-film lead–PDP–lead layered structures are studied in a wide temperature range. At quite high temperatures, current–voltage characteristics are adequately described in terms of the injection current model confirmed by a space charge. At temperatures below ~7.5 K, a number of the sample demonstrate peculiarities that can be explained by the effect of induced superconductivity in a thin film of a conducting polymer included between two massive superconductors (lead).</p>","PeriodicalId":731,"journal":{"name":"Physics of the Solid State","volume":"64 12","pages":"603 - 608"},"PeriodicalIF":0.6,"publicationDate":"2023-03-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"4831925","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Kinetics of Convergence the Si(100) Surface Steps","authors":"M. Yu. Yesin,&nbsp;A. S. Deryabin,&nbsp;A. V. Kolesnikov,&nbsp;A. I. Nikiforov","doi":"10.1134/S1063783422120022","DOIUrl":"10.1134/S1063783422120022","url":null,"abstract":"<p>The convergence kinetics of S_A and S_B steps on Si(100) substrates with inclination of 0.5° and 0.1° are studied. To establish the character of the growth kinetics, the time dependences of the reflection high‑energy electron diffraction (RHEED) intensity are analyzed. It is shown that the convergence rate of the steps in the Si at a growth rate of 0.37 ML/s has a decreasing dependence with an increase temperature. It is found that the rate of formation of a single-domain surface increases with the width of terraces on the surface, which is likely to be related to a partial participation of the growth due to the formation of two-dimensional islands. At temperatures higher 650°С, the dominant growth mode due to the motion of the steps and the rate of formation of the single-domain surface decrease with an increase in the terrace width. Thus, the convergence of single-layer steps is determined by the conditions of the growth of the molecular-beam epitaxy (MBE) and also by the Si(100) substrate orientation. The convergence of S_A and S_B steps of the Si(100) surface is explained by a slow-down motion of S_A which is related to complex mechanisms of permeability and the formation of step kinks. It is assumed that the cause of the slow-down convergence the steps with increasing temperature is an increase in the kink density on the S_A step, which decreases the permeability coefficient of the S_A step.</p>","PeriodicalId":731,"journal":{"name":"Physics of the Solid State","volume":"64 12","pages":"609 - 615"},"PeriodicalIF":0.6,"publicationDate":"2023-03-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"4829480","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Conduction Mechanisms and Thermoelectric Properties of Semimetallic CaSi and CaSi2 Films on Si(100) and Si(111) Substrates","authors":"N. G. Galkin,&nbsp;K. N. Galkin,&nbsp;A. V. Tupkalo,&nbsp;E. Yu. Subbotin,&nbsp;I. M. Chernev,&nbsp;A. V. Shevlyagin,&nbsp;V. V. Khovailo","doi":"10.1134/S1063783422120034","DOIUrl":"10.1134/S1063783422120034","url":null,"abstract":"<p>Nanocrystalline CaSi films with thicknesses from 80 to 130 nm were grown on high-resistance silicon substrates with orientations (111) and (100) by the methods of low-temperature (190–330°C) molecular-beam epitaxy and low-temperature (330°C) solid-phase epitaxy, for which the microstructure, phase composition, and crystal structures were studied. It is found that the polycrystalline, nanocrystalline (NC), and amorphous CaSi and CaSi₂ films are characterized by preferential contribution of holes in the range 1.4–300 K. In magnetic fields 1–4 T and at temperatures 40–100 K, a giant linear magnetoresistive effect (MRE) (to 500%) was observed for the first time in CaSi films with the contribution of another CaSi₂ phase. In CaSi₂ film containing another phase (CaSi), peaks are detected on the temperature dependences of the resistivity and the Hall coefficient that correspond to a phase transition. In addition, in this film, the transition from the positive MRE to negative MRE is observed at <i>Т</i> = 120–200 K. This effect is not observed in the single-phase CaSi₂ film, which corresponds to a certain reconstruction of carrier flows in a magnetic field only in the two-phase system. The study of the thermoelectric properties of CaSi and CaSi₂ films shows that the semimetallic type of the conduction in them leads to the independence of the positive Seebeck coefficient <i>Т</i> = 330–450 K. It is found that the maximum contribution to the Seebeck coefficient and the power factor are observed in the amorphous CaSi film in the case of the presence of some fraction of NC Ca₂Si phase. In the single-phase CaSi₂ films, the Seebeck coefficient and the power factor are halved due to an increase in the hole concentration as compared to the CaSi films.</p>","PeriodicalId":731,"journal":{"name":"Physics of the Solid State","volume":"64 12","pages":"616 - 623"},"PeriodicalIF":0.6,"publicationDate":"2023-03-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"4834302","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Specific Heat of CoFe2O4 and the 0.3CoFe2O4–0.7PbTiO3 Composite","authors":"R. G. Mitarov,&nbsp;S. N. Kallaev,&nbsp;Z. M. Omarov,&nbsp;K. G. Abdulvakhidov","doi":"10.1134/S1063783422110075","DOIUrl":"10.1134/S1063783422110075","url":null,"abstract":"<p>The temperature dependence of the specific heat of the CoFe₂O₄ ferromagnet and the 0.3CoFe₂O₄–0.7PbTiO₃ muliferroic composite is studied in the temperature range 150–820 K. An addition of lead titanate ferroelectric to cobalt ferrite ferromagnet is found to lead to a shift of the magnetic phase transition temperature to lower temperatures by 49 K and to a decrease in the specific heat in a wide temperature range. It is noted that the additional component of the specific heat is due to transitions of cobalt or iron ions to higher energy levels and also due to a distortion of the lattice parameters as a result of formation of three coexisting phases.</p>","PeriodicalId":731,"journal":{"name":"Physics of the Solid State","volume":"64 10","pages":"527 - 530"},"PeriodicalIF":0.6,"publicationDate":"2023-03-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"4094352","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Current Instability of Hardening of a Deformable Medium Element as a Reason of the Neck Propagation","authors":"V. A. Starenchenko,&nbsp;Ya. D. Lipatnikova,&nbsp;Yu. V. Solov’eva,&nbsp;N. N. Belov,&nbsp;L. A. Valuiskaya,&nbsp;I. G. Vovnova","doi":"10.1134/S1063783422110117","DOIUrl":"10.1134/S1063783422110117","url":null,"abstract":"<p>The effect of the current instability of hardening of a deformable medium element on the strain localization at different scale levels has been studied. The current instability term has been taken from the characteristic of the current instability of the electrical conductivity of semiconductors in strong electric fields with a specific <i>I‒V</i> curve [1]. A similar shape of the σ‒ε curve of hardening of a deformable medium element has been considered to be the cause of the strain localization. The strain localization phenomena caused by the current instability of different types have been discussed and modeled. It is shown that the plastic flow scenario under the current instability at the level of a microelement of a medium can manifest itself at the macroscale plastic flow level in the form of localizations of various types. The simulation within a two-level finite element model proposed previously in [2] has been carried out. The cases of a stable neck or neck propagation at the macrolevel under the uniaxial tension of a sample have been observed, depending on the shape of the hardening curves of the unit volume of a deformed sample similar the current instability curves.</p>","PeriodicalId":731,"journal":{"name":"Physics of the Solid State","volume":"64 11","pages":"555 - 560"},"PeriodicalIF":0.6,"publicationDate":"2023-03-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"4094948","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Luminescent Properties of Yttrium–Scandium Phosphate Solid Solutions Doped with Europium Ions","authors":"V. S. Voznyak-Levushkina,&nbsp;A. A. Arapova,&nbsp;D. A. Spassky,&nbsp;I. V. Nikiforov,&nbsp;B. I. Zadneprovski","doi":"10.1134/S1063783422110130","DOIUrl":"10.1134/S1063783422110130","url":null,"abstract":"<p>The luminescent properties of Y_1 – _<i>x</i>Sc_<i>x</i>PO₄: 0.5 mol % Eu³⁺ (<i>x</i> = 0, 0.2, 0.4, 0.5, 0.6, 0.8, 1) solid solutions are studied at the excitation by the radiations of ultraviolet and vacuum-ultraviolet ranges. The disordering of the solid-solution crystal structure is shown to influence the structure of the Eu³⁺ luminescence spectra. The bandgap width is shown to nonlinearly depend on the solid solution composition. The model explaining this effect is proposed.</p>","PeriodicalId":731,"journal":{"name":"Physics of the Solid State","volume":"64 11","pages":"567 - 575"},"PeriodicalIF":0.6,"publicationDate":"2023-03-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"4436818","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Change in Elastic Deformations in SiC Films during Their Growth by the Coordinated Atomic Substitution Method on Si Substrates","authors":"Yu. A. Eremeev,&nbsp;M. G. Vorobev,&nbsp;A. S. Grashchenko,&nbsp;A. V. Semencha,&nbsp;A. V. Osipov,&nbsp;S. A. Kukushkin","doi":"10.1134/S1063783422110038","DOIUrl":"10.1134/S1063783422110038","url":null,"abstract":"<p>Consecutive stages of synthesizing epitaxial SiC films on <i>n</i>-type Si(111) and <i>p</i>-type Si(111) surfaces in a mixture of gaseous carbon monoxide and silane are studied by X-ray diffraction and Raman scattering methods. In films grown on an <i>n</i>-type Si(111) surface, only weak elastic deformations are observed during synthesis; however, in films grown on <i>p</i>-type Si substrates, relatively strong elastic deformations form, which are completely relaxed by the 40th min. It is found that the film structure is sharply changed at the third minute of the growth, which is related to the formation and growth of pores in the SiC layer. The differences of the lattice parameters of SiC films grown on <i>n</i>-Si and <i>p</i>-Si substrates are determined and confirmed by analyzing the change in the curvatures of the SiC/Si plates.</p>","PeriodicalId":731,"journal":{"name":"Physics of the Solid State","volume":"64 9","pages":"511 - 515"},"PeriodicalIF":0.6,"publicationDate":"2023-03-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"4094013","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Accumulation of Defects under Plastic Deformation of Polycrystalline Copper-Based Alloys","authors":"L. I. Trishkina,&nbsp;T. V. Cherkasova,&nbsp;A. N. Solov’ev,&nbsp;N. V. Cherkasov","doi":"10.1134/S1063783422110129","DOIUrl":"10.1134/S1063783422110129","url":null,"abstract":"<p>The paper presents the experimental investigation of the role of the size factor in the formation of the defect structure of metallic materials. The objects of study were polycrystalline FCC Cu–Al and Cu–Mn solid solutions with average grain sizes of 10–240 µm. The dislocation structure of foil samples subjected to various deformations at room temperature was studied by TEM. We measured the scalar dislocation density (ρ), the density of geometrically necessary dislocations (GND) (ρ_g), the density of statistically stored dislocations (SSD) (ρ_s), the curvature-torsion of the crystal lattice (χ), and some other parameters. The effect of the grain size of the dislocation substructure on its parameters has been quantitatively studied. The sources of curvature-torsion χ of the crystal lattice were determined from electron microscopic images. We measured χ in the alloys under study from different sources and its change with distance (<i>x</i>) from the source for alloys with fixed grain size and degree of deformation. The change in the average value of curvature-torsion from all sources with the degree of deformation is considered.</p>","PeriodicalId":731,"journal":{"name":"Physics of the Solid State","volume":"64 11","pages":"561 - 566"},"PeriodicalIF":0.6,"publicationDate":"2023-03-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"4094932","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}